question about my new Supermax 19x38

I picked up a new Supermax 19×38, love it so far. But I do have a small issue. I run about 3 end grain cutting boards through it and the paper rips on one of the ends. I have been through about 4 strips of sandpaper so far. I make sure it is on tight. I run 1 board through it and then re-tighten it, due to the stretch of it heating up. It still ends up ripping. I am wasting good sand paper. Any suggestions ?? Maybe it just heats up too fast an I don’t give the paper time to cool down between boards? help…

13 replies so far

There are a lot of possible causes here, but what sticks in my head is the phrase “I run 1 board through it and then re-tighten it, due to the stretch of it heating up.”

When I do end grain cutting board sanding on my smaller Performax 16-32, the paper and drum stay relatively cool. If things show signs of heating up, I’ll back off on the cuts.

Typically a freshly glued up board will get a scrubbing with a scraper to remove most of the glue squeeze out followed by a few passes with the hand held belt sander to even things out a bit. It is not unusual to have the high/low spots separate by 1/8”.

The first passes with the drum sander are with 36 grit, advancing the cut no more that 1/4 turn (1/64”) each pass.The board is flipped each pass. I’ve noticed that boards thinner than 1” often will warp from the heat and can bind up and literally burn if I try to too much too fast.

Once I get an even surface, I’ll pass with 80, 120, then 180 using very light cuts (1/8 turn). The polishing is done with a ROS, beginning with 100 grit to eliminate the visible straight lines left by the drum sanders 180 grit.Depending on the wood, I’ll usually stop with 220 or 320 grit.

I ask this out of ignorance regarding that particular sander. Does it actually use paper backed abrasives? My Jet uses cloth backed strips and they are really, really tough. I haven’t seen any sign of weakening at the ends where they attach to the drum. The Jet does have a special clip mechanism to take up the slack as the belt expands.

The comments above on how aggressive you are in trying to remove material are all spot on.

As far as heat generation, there are two factors at play; the depth of “cut” and the feed rate. Too slow of a feed rate results in a lot of heat build up. Try less aggressive cuts and up the feed rate a bit to see if that helps. You should feel the surface of the piece as it exits the machine to gauge how you are doing.

A final thought. What are you using for dust collection? A big collector with high air flow helps to cool off the sanding drum.

thanks for the suggestions. It does use cloth backed strips, not paper, my bad. I will try backing off the depth of the cut. I have the feed rate at 10 and then let the smart sand feature slow it down as needed. I use a jet dust collector which seems to be doing just fine. Now i just need to replace the sandpaper that I ruined, where’s the best inexpensive place?

If you are allowing the smart sand to adjust the feed rate then you are being WAY too aggressive! That feature is meant to keep you out of real trouble with overloading the machine, not set the optimal feed rate.

Back WAY off on your depth and work with the feed rate to get better results. Note that it sometimes helps to send the piece thorough multiple times without adjusting the depth. Give it a try. You will hear the sound of the sanding drum doing its work on each pass. Rotate the workpiece and / or send it through on an angle. Sanding end grain is hard work for any type of sander. You have to give it some time.

Someone on the forum suggested industrialabrasives.com as a good source. I bought several rolls in several different grits from them. Their product works fine. I really don’t know if it is the cheapest, the best, or the worst. It’s just what I bought and it works. I have purchased a lot of abrasives from Klingspor in the past. Their logo is on the rolls that came with my Jet sander.

Oh! A note added later: do you clean your abrasives? You really should have one of those big “eraser” things made for cleaning abrasives. The grit on the drum will clog easily, especially with glue. You can easily see this and you can also see the burn marks the clogged abrasive leaves on the workpiece. Open the hood, turn on the motor, and CAREFULLY run the eraser along the drum. You will see the difference in colors immediately as the build up is removed. Stop the motor and use a brush to get any residue off. Get any junk that falls on the feed belt swept off too. Same goes for belt sanders and even random orbit sanders. Cleaning the abrasive gives you much better sanding results and greatly extends the useful life of the expensive abrasives. The cleaner gizmo I use I bought probably more than a dozen years ago for probably less than ten bucks. Great investment.

Another comment on buying abrasives. You can get strips with pre-cut ends, ready to wrap on the drum. Do not waste your money on this. It is trivial to take an existing strip as a template and a utility knife to trim your own ends.

One gripe I do have is that the rolls come in a few arbitrary lengths. The long ones are close to a lifetime supply and are a big investment. The smaller (30’ or so) rolls don’t break the bank, but for my machine they amount to about four useful pieces and an additional piece that is just a little too short to use. Probably about 15 – 20% waste. I am certain that the guys selling this stuff are well aware of just how long a piece you need and they could offer their product in a length that matches the common machine requirements.

I just bought the same sander and agree with Kazooman on the smart sand. If you are using that then you are way to aggressive. I just ran an entire set of stair treads thru mine when it came out of the box with the factory installed 80 grit. Cleaned the drum with an eraser every few boards and it ran fine.

-- All tyranny needs to gain a foothold is for people of good conscience to remain silent - Thomas Jefferson

I have that sander too…it is awesome, but I will “pile-on” and say that you are being too aggressive. I rarely turn it down more than a 1/8 or 1/16th turn when sanding. The intelli-sand is made as a last resort to save the machine…..I have only triggered it maybe twice.

Also, tighten the paper originally, then maybe once after that and that should be sufficient. I have never ripped the paper, but I have put a sappy line in it that will burn the wood. I posted asking about that and got some great suggestions that worked.

I have frequently bought from klingspor. They are a great and very reasonably priced outlet, but I have always bought the supermax paper from our local Acme tool. Not for any particular reason, other than I wanted to do some local business to keep them solvent.

One thing I have to keep telling myself, is this is not a thickness planer…go slow…..Just my .02Mike

PS…the paper while it may be ripped can still be used…..I have used the worn paper for lathe projects and it works well!!!